According to my results, restoration that is based on emulating natural disturbances and natural ecological processes provides promising results in terms of bringing back some of the key structural attributes in previously managed forests. However, a more challenging question is whether the restored structures can also aid in the restoration of threatened species over time. In this context, at least two aspects must be considered. Firstly, the inherent variability in forests is difficult to re-create using purely artificial treatments.
Secondly, to fully determine how species respond to increased structural heterogeneity a longer time-scale (than the 10 year period examined in this thesis) is required.
My results emphasize the challenges faced in the restoration of forests based on natural disturbance emulation. In fact, natural disturbances are often complex phenomena leading to wide variation in forest structures and processes. In practice, this implies that combinations and compromises are also necessary. Of the treatments included in this thesis, the use of prescribed fire is perhaps the closest analog to a natural disturbance, although its effects can be expected to differ markedly from wildfires that have a greater variability in their extent and severity (Zackrisson 1977; Pennanen 2002; Kuuluvainen & Aakala 2011).
Therefore, if high-intensity crown fires cannot be prescribed, as they are often difficult to control, it is advisable to kill some of the trees prior to burning the forests, either by the creation of canopy gaps or by thinning the forests to varying degrees (I).
The situation is slightly different in canopy gaps that are created without fire by cutting the trees; without available seedbeds, the increase in above-ground resources does not compensate for the missing variation in ground microtopography (II). This missing factor could, therefore, be replaced by artificially exposing the mineral soil from small patches (II). To better capture all the variation in pit-and-mound microtopography, an alternative would be to artificially uproot the trees when canopy openings are created (Hekkala et al.
2014). Heterogeneity should also be the target in tree-level treatments where various mortality factors are emulated; to account for the natural variation in dead wood, different methods should probably be used together, to provide substrates for species with different life-history strategies and substrate requirements (Berglund et al. 2011; Eriksson et al.
2013; Komonen et al. 2014).
Since much of the variation in structural heterogeneity is connected with successional processes, both in dead and living trees, it takes time for these successions to reach more advanced stages. For this reason, it is challenging to create variation in the decay stages of restored dead wood (III) or to create a multi-cohort age-class structure of trees in the short-term (II). These can only develop with time. Moreover, the historical use of the ecosystem
and its surrounding landscape can be expected to have an effect on the ability of species to colonize the forest. The further the structures, and hence the source populations, are from natural forests, the longer it will take for the species to appear in the restored forest.
5. CONCLUDING REMARKS
Natural and anthropogenic disturbances form a continuum in their level of naturalness, and all disturbance-based treatments can be placed at some point along this continuum. The closer the treatments are to natural disturbances, and the closer the current forest structure is to a natural one, the more likely that the structures and species in the forest can be restored.
How closely natural disturbances can be emulated in the current forest structure will depend on the management objective. Given the lack of detailed knowledge on species-level responses to restoration, the safest strategy would be to emulate natural disturbances as closely as is practically possible, as we can expect that the species will have adapted to, or can benefit from, these disturbances. Such a strategy could be used in protected areas, where the main function is to provide habitats for endangered species that cannot survive in managed forests. In forests where the main function is to produce timber, disturbances cannot be closely emulated due to different management goals. However, some restorative actions – such as prescribed burning and increasing the amount of dead wood – may also be applied in managed forests, to facilitate emulation of natural disturbances and to maintain biodiversity.
Although the evidence I have gathered in this thesis show the clear positive effects that restoration has on the re-creation of naturally occurring forest characteristics, restoration of the full array of structural heterogeneity of natural forests appears to be difficult with the methods that are currently applied. The discrepancy in the structures between natural and managed forests, however, can be greatly diminished with careful planning of the restoration treatments. A particular challenge comes from inherently long processes that create and maintain the ecological structures in boreal forest ecosystems, including the generally slow process of stand succession or wood decay. Some of my results are clearly limited due to the relatively short monitoring period. Whether the situation will change as time passes can only be answered by longer-term monitoring of the restored forests.
REFERENCES
Attiwill P.M. (1994). The disturbance of forest ecosystems: the ecological basis for conservative management. Forest Ecology and Management 63: 247–300.
https://doi.org/10.1016/0378-1127(94)90114-7.
Axelsson E.P., Lundmark T., Högberg P., Nordin A. (2014). Belowground competition directs spatial patterns of seedling growth in boreal pine forests in Fennoscandia. Forests 5:
2106-2121. https://doi.org/10.3390/f5092106.
Baldrian P. (2008). Enzymes of saprotrophic basidiomycetes. In: Boddy L., Frankland J., Van West P. (ed.). Ecology of saprotrophic basidiomycetes. Academic Press, London, UK.
p. 19–41. https://doi.org/10.1016/S0275-0287(08)80004-5.
Belyea L.R., Lancaster J. (1999). Assembly rules within a contingent ecology. Oikos 86:
402-416. https://doi.org/10.2307/3546646.
Berglund H., Jönsson M.T., Penttilä R., Vanha-Majamaa I. (2011). The effects of burning and dead-wood creation on the diversity of pioneer wood-inhabiting fungi in managed boreal spruce forests. Forest Ecology and Management 261: 1293–1305.
https://doi.org/10.1016/j.foreco.2011.01.008.
Björkman E., Lundeberg G. (1971). Studies on root competition in a poor pine forest by supply of labeled nitrogen and phosphorus. Studia Forestalia Suecica 94:1–16.
Brandt J.P., Flannigan M.D., Maynard D.G., Thompson I.D., Volney W.J.A. (2013). An introduction to Canada’s boreal zone: ecosystem processes, health, sustainability, and environmental issues. Environmental Reviews 21: 207-226. https://doi.org/10.1139/er-2013-0040.
Boddy L., Heilmann-Clausen J. (2008). Basidiomycete community development in temperate angiosperm wood. In: Boddy L., Frankland J., Van West P. (ed.). Ecology of saprotrophic basidiomycetes. Academic Press, London, United Kingdom. p. 211–237.
https://doi.org/10.1016/S0275-0287(08)80014-8.
Brūmelis G., Jonsson B.G., Kouki J., Kuuluvainen T., Shorohova E. (2011). Forest naturalness in northern Europe: perspectives on processes, structures and species diversity.
Silva Fennica 45: 785–806. https://doi.org/10.14214/sf.446.
Burton P.J., Messier C., Smith D.W., Adamowicz W.L. (ed.). (2003). Towards sustainable management of the boreal forest. NRC Research Press, Ottawa, Ontario, Canada. 1039 p.
Burton P.J., Messier C., Adamowicz W.L., Kuuluvainen T. (2006). Sustainable management of Canada's boreal forests: Progress and prospects. Ecoscience 13: 234–248.
https://doi.org/10.2980/i1195-6860-13-2-234.1.
Cajander A.K. (1949). Forest types and their significance. Acta Forestalia Fennica 56: 1–
71. https://doi.org/10.14214/aff.7396.
Cardinale B.J., Duffy J.E., Gonzalez A., Hooper D.U., Perrings C., Venail P., Narwani A., Mace G.M., Tilman D., Wardle D.A., Kinzig A.P., Gretchen C.D., Loreau M., Grace J.B., Larigauderie A., Srivastava D.S., Naeem S. (2012). Biodiversity loss and its impact on humanity. Nature 486: 59–67. https://doi.org/10.1038/nature11148.
Ceballos G., Ehrlich P.R., Barnosky A.D., García A., Pringle R.M., Palmer T.M. (2015).
Accelerated modern human–induced species losses: Entering the sixth mass extinction.
Science Advances 1: e1400253. https://doi.org/10.1126/sciadv.1400253.
Certini G. (2005). Effects of fire on properties of forest soils: a review. Oecologia 143: 1–
10. https://doi.org/10.1007/s00442-004-1788-8.
Cooke R.C., Rayner A.D. (1984). Ecology of saprotrophic fungi. Longman, New York, USA.
de Chantal M., Lilja-‐Rothsten S., Peterson C., Kuuluvainen T., Vanha-‐Majamaa I., Puttonen, P. (2009). Tree regeneration before and after restoration treatments in managed boreal Picea abies stands. Applied Vegetation Science 12: 131–143.
https://doi.org/10.1111/j.1654-109X.2009.01004.x.
Djupström L.B., Weslien J., ten Hoopen J. Schroeder L.M. (2012). Restoration of habitats for a threatened saproxylic beetle species in a boreal landscape by retaining dead wood on
clear-cuts. Biological conservation 155: 44–49.
https://doi.org/10.1016/j.biocon.2012.06.009.
Ellis E.C., Ramankutty N. (2008). Putting people in the map: anthropogenic biomes of the world. Frontiers in Ecology and the Environment 6: 439–447.
https://doi.org/10.1890/070062.
Ellis E.C. (2011). Anthropogenic transformation of the terrestrial biosphere. Philosophical Transactions of the Royal Society of London A: Mathematical, Physical and Engineering Sciences 369: 1010–1035. https://doi.org/10.1098/rsta.2010.0331.
Eriksson A.M., Olsson J., Jonsson, B.G., Toivanen S. Edman, M. (2013). Effects of restoration fire on deadwood heterogeneity and availability in three Pinus sylvestris forests in Sweden. Silva Fennica 47: article id 954. https://doi.org/10.14214/sf.954.
Esseen P.A., Ehnström B., Ericson L., Sjöberg K. (1997). Boreal forests. Ecological Bulletins: 16–47.
Filotas E., Parrott L., Burton P.J., Chazdon R.L., Coates K.D., Coll L., Haeussler S., Martin K., Nocentini S., Puettmann K.J., Putz F.E., Simard S.W., Messier C. (2014). Viewing forests through the lens of complex systems science. Ecosphere 5: 1–23.
https://doi.org/10.1890/ES13-00182.1.
Gauthier S., Vaillancourt M-A., Leduc A., De Grandpré L., Kneeshaw D., Morin H., Drapeau P., Bergeron Y. (ed.). (2009). Ecosystem Management in the boreal forest. Presses de l’Université du Québec, Québec, Canada.
Gauthier S., Bernier P., Kuuluvainen T., Shvidenko A.Z., Schepaschenko D.G. (2015).
Boreal forest health and global change. Science 349: 819–822.
https://doi.org/10.1126/science.aaa9092.
Gromtsev A. (2002). Natural disturbance dynamics in the boreal forests of European Russia: a review. Silva Fennica 36: 41–55. https://doi.org/10.14214/sf.549.
Halme P., Allen K.A., Auniņš A., Bradshaw R.H.W., Brūmelis G., Čada V., Clear J.L, Eriksson A-M., Hannon G., Hyvärinen E., Ikauniece S., Iršėnaitė R., Jonsson B.G., Junninen K., Kareksela S., Komonen A., Kotiaho J.S., Kouki J., Kuuluvainen T., Mazziotta A., Mönkkönen M., Nyholm K., Oldén A., Shorohova E., Strange N., Toivanen T., Vanha-Majamaa I., Wallenius T., Ylisirniö A-L., Zin E. (2013). Challenges of ecological restoration: lessons from forests in northern Europe. Biological Conservation 167: 248–
256. https://doi.org/10.1016/j.biocon.2013.08.029.
Harmon M.E., Franklin J.F., Swanson F.J., Sollins P., Gregory S.V., Lattin J.D., Anderson N.H., Cline S.P., Aumen N.G., Sedell J.R., Lienkaemper G.W., Cromack Jr. K., Cummins K.W. (1986). Ecology of coarse woody debris in temperate ecosystems. Advances in Ecological Research 15: 133–302. https://doi.org/10.1016/S0065-2504(08)60121-X.
Heikkala O., Martikainen P., Kouki J. (2016). Decadal effects of emulating natural disturbances in forest management on saproxylic beetle assemblages. Biological Conservation 194: 39–47. https://doi.org/10.1016/j.biocon.2015.12.002.
Hekkala A-M., Tarvainen O., Tolvanen, A. (2014). Dynamics of understory vegetation after restoration of natural characteristics in the boreal forests in Finland. Forest Ecology and Management 330: 55–66. https://doi.org/10.1016/j.foreco.2014.07.001.
Hekkala A-M., Ahtikoski A., Päätalo M.L., Tarvainen O., Siipilehto J., Tolvanen A. (2016).
Restoring volume, diversity and continuity of deadwood in boreal forests. Biodiversity and conservation 25: 1107–1132. https://doi.org/10.1007/s10531-016-1112-z.
Henttonen H.M., Nöjd P., Mäkinen, H. (2017). Environment-induced growth changes in the Finnish forests during 1971–2010 – An analysis based on National Forest Inventory. Forest Ecology and Management 386: 22–36. https://doi.org/10.1016/j.foreco.2016.11.044.
Hunter M. L. (ed.) (1999). Maintaining biodiversity in forest ecosystems. Cambridge University Press, UK. https://doi.org/10.1017/CBO9780511613029.
Hyvärinen E., Kouki J., Martikainen P., Lappalainen H. (2005). Short-term effects of controlled burning and green-tree retention on beetle (Coleoptera) assemblages in managed boreal forests. Forest Ecology and Management 212: 315–332.
https://doi.org/10.1016/j.foreco.2005.03.029.
IUCN. (2016). The IUCN Red List of Threatened Species. Version 2016-3. Online at:
http://www.iucnredlist.org.
Johann E. (2006). Historical development of nature-based forestry in Central Europe. In:
Diaci J. (ed.). Nature-based forestry in central Europe. Alternatives to industrial forestry and strict preservation. Studia Forestalia Slovenica. Department of Forestry and Renewable Forest Resources – Biotechnical Faculty. p. 1–17
Jonsson B.G., Kruys N., Ranius T. (2005). Ecology of species living on dead wood – lessons for dead wood management. Silva Fennica 39: 289–309.
https://doi.org/10.14214/sf.390.
Junninen K., Komonen A. (2011). Conservation ecology of boreal polypores: a review.
Biological Conservation 144: 11–20. https://doi.org/10.1016/j.biocon.2010.07.010.
Kimmins J.P. (2004). Forest ecology: a foundation for sustainable forest management and environmental ethics in forestry. Third Edition. Prentice Hall, NJ.
https://doi.org/10.1002/9780470995242.ch2.
Kohm K.A., Franklin J.F. (eds) (1997). Creating a forestry for the 21st century: The science of ecosystem management. Island Press, California, USA.
Kalela E. K. (1948). Luonnonmukainen metsien käsittely. Silva Fennica 64: 16–32.
https://doi.org/10.14214/sf.a13987.
Koivula M., Kuuluvainen T., Hallman E., Kouki J., Siitonen J., Valkonen S. (2014). Forest management inspired by natural disturbance dynamics (DISTDYN) a long-term research and development project in Finland. Scandinavian Journal of Forest Research 29: 579–592.
https://doi.org/10.1080/02827581.2014.938110
Komonen A., Halme P., Jäntti M., Koskela T., Kotiaho J.S., Toivanen T. (2014). Created substrates do not fully mimic natural substrates in restoration: the occurrence of polypores on spruce logs. Silva Fennica 48: article id 980. https://doi.org/10.14214/sf.980.
Kouki J., Hyvärinen E., Lappalainen H., Martikainen P., Similä M. (2012). Landscape context affects the success of habitat restoration: large-‐scale colonization patterns of saproxylic and fire-‐associated species in boreal forests. Diversity and Distributions 18:
348–355. https://doi.org/10.1111/j.1472-4642.2011.00839.x.
Kotiranta H., Junninen K., Saarenoksa R., Kinnunen J., Kytövuori I. (2010). Kääväkkäät.
Aphyllophorales & Heterobasidiomycetes. In: Rassi P., Hyvärinen E., Juslén A., Mannerkoski I. (ed.) The 2010 Red List of Finnish species. Ympäristöministeriö & Suomen ympäristökeskus. p. 249–263.
Kraft N.J., Adler P.B., Godoy, O., James, E.C., Fuller, S., Levine, J.M. (2015). Community assembly, coexistence and the environmental filtering metaphor. Functional Ecology 29:
592–599. https://doi.org/10.1111/1365-2435.12345.
Kuuluvainen T. (2002). Natural variability of forests as a reference for restoring and managing biological diversity in boreal Fennoscandia. Silva Fennica 36: 97–125.
https://doi.org/10.14214/sf.552.
Kuuluvainen T., Aakala T. (2011). Natural forest dynamics in boreal Fennoscandia: a review and classification. Silva Fennica 45: 823–841. https://doi.org/10.14214/sf.73.
Kuuluvainen T., Ylläsjärvi I. (2011). On the natural regeneration of dry heath forests in Finnish Lapland: a review of VT Aaltonen (1919). Scandinavian Journal of Forest Research 26: 34–44. https://doi.org/10.1080/02827581.2011.517951.
Kuuluvainen T., Tahvonen O., Aakala T. (2012). Even-aged and uneven-aged forest management in boreal Fennoscandia: a review. Ambio 41: 720–737.
https://doi.org/10.1007/s13280-012-0289-y.
Kuuluvainen T., Grenfell R. (2012). Natural disturbance emulation in boreal forest ecosystem management – theories, strategies, and a comparison with conventional even-aged management. Canadian Journal of Forest Research 42: 1185–1203.
https://doi.org/10.1139/x2012-064.
Kuuluvainen T. (2017). Ecosystem management of the boreal forest. Oxford Research
Encyclopedia of Environmental Science.
http://environmentalscience.oxfordre.com/view/10.1093/acrefore/9780199389414.001.0001 /acrefore-9780199389414-e-15. [Cited 22 May 2017].
Kuusipalo J. (1996). Suomen metsätyypit. Kirjayhtymä Oy, Rauma, Finland.
Kubartová A., Ottosson E., Dahlberg A., Stenlid J. (2012). Patterns of fungal communities among and within decaying logs, revealed by 454 sequencing. Molecular Ecology 21:
4514–4532. https://doi.org/10.1111/j.1365-294X.2012.05723.x.
Landres P. B., Morgan P., Swanson F.J. (1999). Overview of the use of natural variability concepts in managing ecological systems. Ecological Applications 9: 1179–1188.
Lehto J. (1956). Tutkimuksia männyn luontaisesta uudistumisesta Etelä-Suomen kangasmailla. Acta Forestalia Fennica 66: 1–106. https://doi.org/10.14214/aff.7472.
Mäkinen H., Hynynen J., Siitonen J., Sievänen R. (2006). Predicting the decomposition of Scots pine, Norway spruce, and birch stems in Finland. Ecological Applications 16: 1865–
1879. https://doi.org/10.1890/1051-0761(2006)016[1865:PTDOSP]2.0.CO;2.
Messier C., Puettmann K., Coates D. (2013). Managing forests as complex adaptive systems: building resilience to the challenge of global change. Routledge, New York, USA.
Mönkkönen M. (2004). Suomen metsäluonto – osa globaalia monimuotoisuutta. In:
Kuuluvainen T., Saaristo L., Keto-Tokoi P., Kostamo J., Kuuluvainen J., Ollikainen M.
Salpakivi-Salomaa P. (ed.). Metsän kätköissä – Suomen metsäluonnon monimuotoisuus.
Edita Publishing Oy, Helsinki, Finland. p. 19–47.
Morgenstern E. K. (2007). The origin and early application of the principle of sustainable forest management. The Forestry Chronicle 83: 485–489. https://doi.org/10.5558/tfc83485-4.
Mori A.S., Lertzman K.P., Gustafsson L. (2017). Biodiversity and ecosystem services in forest ecosystems: a research agenda for applied forest ecology. Journal of Applied Ecology 54: 12–27. https://doi.org/10.1111/1365-2664.12669.
Niemelä T., Renvall P., Penttilä R. (1995). Interactions of fungi at late stages of wood decomposition. Annales Botanici Fennici 32: 141–152.
Niemelä T. (2011). Kääpien mikroskooppinen määritys. Helsingin yliopiston kasvitieteen monisteita 193: 1–92.
Niemelä T. (2016). Suomen käävät. Norrlinia 31: 1–432.
Norros V., Penttilä R., Suominen M., Ovaskainen O. (2012). Dispersal may limit the occurrence of specialist wood decay fungi already at small spatial scales. Oikos 121: 961–
974. https://doi.org/10.1111/j.1600-0706.2012.20052.x.
Ottosson E., Kubartová A., Edman M., Jönsson M., Lindhe A., Stenlid J., Dahlberg A.
(2015). Diverse ecological roles within fungal communities in decomposing logs of Picea abies. FEMS Microbiology Ecology: 91.
Ottosson E. (2013). Succession of wood-inhabiting fungal communities – diversity and species interactions during the decomposition of Norway spruce. PhD thesis, Swedish University of Agricultural Sciences, Uppsala. https://doi.org/10.1093/femsec/fiv012.
Pickett S., Cadenasso M. L., Meiners S.J. (2009). Ever since Clements: from succession to vegetation dynamics and understanding to intervention. Applied Vegetation Science 12: 9–
21. https://doi.org/10.1111/j.1654-109X.2009.01019.x.
Pennanen J. (2002). Forest age distribution under mixed-severity fire regimes – a simulation- based analysis for middle boreal Fennoscandia. Silva Fennica 36: 213–231.
https://doi.org/10.14214/sf.559.
Perera A.H., Buse L.J., Weber M.G. (ed.). (2004). Emulating natural forest landscape disturbances: concepts and applications. Columbia University Press, New York, USA.
Pitkänen A., Järvinen E., Turunen J., Kolström T., Kouki J. (2005). Kulotuksen ja maan muokkauksen vaikutus männyn siementen itämiseen ja kylvötaimien varhaiseen eloonjääntiin. Metsätieteen aikakauskirja 4/2005: 387–397.
Puettmann K. J., Coates K. D., Messier C.C. (2008). A critique of silviculture: managing for complexity. Island Press, Washington, USA.
Rajala T., Peltoniemi M., Pennanen T., Mäkipää R. (2012). Fungal community dynamics in relation to substrate quality of decaying Norway spruce (Picea abies [L.] Karst.) logs in boreal forests. FEMS Microbiology Ecology 81: 494–505. https://doi.org/10.1111/j.1574-6941.2012.01376.x.
Rassi P., Hyvärinen E., Juslén A., Mannerkoski I. (ed.). (2010). The 2010 Red List of Finnish species. Ympäristöministeriö & Suomen ympäristökeskus, Helsinki, Finland.
Raunio A., Schulman A., Kontula T. (ed.). 2008. Suomen luontotyyppien uhanalaisuus.
Helsinki, Suomen ympäristökeskus. Suomen ympäristö 8/2008.
Renvall P. (1995). Community structure and dynamics of wood-rotting Basidiomycetes on decomposing conifer trunks in northern Finland. Karstenia 35: 1–51.
Rodríguez A., Kouki J. (2015). Emulating natural disturbance in forest management enhances pollination services for dominant Vaccinium shrubs in boreal pine-dominated
forests. Forest Ecology and Management 350: 1–12.
https://doi.org/10.1016/j.foreco.2015.04.029.
Rouvinen S., Kouki, J. (2008). The natural northern European boreal forests: unifying the concepts, terminologies, and their application. Silva Fennica 42: 135–146.
https://doi.org/10.14214/sf.270.
SER. (2004). Society for Ecological Restoration International Science & Policy Working Group: The SER International Primer on Ecological Restoration. Society for Ecological Restoration International.
Seibold S., Bässler C., Brandl R., Büche B., Szallies A., Thorn S., Ulyshen, M.D., Müller J.
(2016). Microclimate and habitat heterogeneity as the major drivers of beetle diversity in dead wood. Journal of Applied Ecology 53: 934–943. https://doi.org/10.1111/1365-2664.12607.
Shorohova E., Kneeshaw D., Kuuluvainen T., Gauthier S. (2011). Variability and dynamics of old-growth forests in the circumboreal zone: implications for conservation, restoration and management. Silva Fennica 45: 785–806. https://doi.org/10.14214/sf.72.
Siitonen J. (2001). Forest management, coarse woody debris and saproxylic organisms: 670 Fennoscandian boreal forests as an example. Ecological Bulletins 49: 11–41.
Similä M., Junninen K. (ed.). (2012). Ecological restoration and management in boreal forests: best practices from Finland. Metsähallitus, Natural Heritage Services, Vantaa, Finland.
Sloan S., Sayer J.A. (2015). Forest Resources Assessment of 2015 shows positive global trends but forest loss and degradation persist in poor tropical countries. Forest Ecology and Management 352: 134–145. https://doi.org/10.1016/j.foreco.2015.06.013.
Stenlid J., Penttilä R., Dahlberg A. (2008). Wood-decay Basidiomycetes in boreal forests:
distribution and community development. In: Boddy L., Frankland J., Van West P. (ed.).
Ecology of saprotrophic basidiomycetes. Academic Press, London, UK. p. 239–261.
https://doi.org/10.1016/S0275-0287(08)80015-X.
Stokland J.N., Siitonen J., Jonsson B.G. (2012). Biodiversity in dead wood. Cambridge University Press, New York, USA. https://doi.org/10.1017/CBO9781139025843.
Suominen M., Junninen K., Heikkala O. Kouki J. (2015). Combined effects of retention forestry and prescribed burning on polypore fungi. Journal of Applied Ecology 52: 1001–
1008. https://doi.org/10.1111/1365-2664.12447.
Tasanen T., (2004). Läksi puut ylenemähän. Metsien hoidon historia Suomessa keskiajalta metsäteollisuuden läpimurtoon 1870-luvulla. Summary: The history of silviculture in Finland from the Mediaeval to the breakthrough of forest industry in 1870s.
Metsäntutkimuslaitoksen tiedonantoja 920. Metsäntutkimuslaitos, Vammala, Finland.
Tikkanen O–P., Martikainen P., Hyvärinen E., Junninen K., Kouki J. (2006). Red-listed boreal forest species of Finland: associations with forest structure, tree species, and decaying wood. Annales Zoologici Fennici 43: 373-383.
Walker B., Holling C.S., Carpenter S., Kinzig A. (2004). Resilience, adaptability and transformability in social–ecological systems. Ecology and Society 9, 5.
https://doi.org/10.5751/ES-00650-090205.
Walters C.J., Holling C.S. (1990). Large-‐scale management experiments and learning by doing. Ecology 71: 2060–2068. https://doi.org/10.2307/1938620.
Williams B.K. (2011). Adaptive management of natural resources–framework and issues.
Journal of Environmental Management 92: 1346–1353.
https://doi.org/10.1016/j.jenvman.2010.10.041.
Wright D.H. (1983). Species-energy theory: an extension of species-area theory. Oikos 41:
496–506. https://doi.org/10.2307/3544109.
Yli-Vakkuri P. (1961). Emergence and initial development of tree seedlings on burnt-over forest land. Acta Forestalia Fennica 74: 1–50. https://doi.org/10.14214/aff.7128.
Zackrisson O. (1977). The influence of forest fires in the North Swedish boreal forest.
Oikos 29: 22–32. https://doi.org/10.2307/3543289.